U.S. patent number 4,591,691 [Application Number 06/665,983] was granted by the patent office on 1986-05-27 for auxiliary electric heating system for internal combustion engine powered vehicles.
Invention is credited to Edward A. Badali.
United States Patent |
4,591,691 |
Badali |
May 27, 1986 |
Auxiliary electric heating system for internal combustion engine
powered vehicles
Abstract
An auxiliary heating system for an internal combustion engine
powered vehicle having a coolant system in which the conventional
engine coolant pump circulates heated coolant from the engine to a
heater radiator for transferring heat from the coolant to the
vehicle passenger compartment includes a thermostatically
controlled electric heating element and an electric pump located in
a branch conduit receiving coolant from the heater radiator. The
heating element and electric pump are selectively energizable by
the vehicle operator to heat and circulate the engine coolant
through a check valve and then through selectively actuated
electrically controlled valves which direct it through the heater
radiator, the engine or both when the engine is not running. The
check valve isolates the heating element and electric pump from
normal engine coolant circulation flow when the engine is running.
In another embodiment an electrically controlled valve replaces the
check valve for the same purpose. The auxiliary heating system may
receive electric power from an AC source external to the vehicle
and may adapt the AC power for operation of the electric blower
conventionally associated with the vehicle's heater radiator. The
engine may be precluded from being started when the electric
heating element or electric pump are energized.
Inventors: |
Badali; Edward A. (Hamden,
CT) |
Family
ID: |
24672344 |
Appl.
No.: |
06/665,983 |
Filed: |
October 29, 1984 |
Current U.S.
Class: |
219/202;
123/142.5E; 219/208; 237/12.3B; 392/307 |
Current CPC
Class: |
B60H
1/034 (20130101); F01P 3/20 (20130101); F01P
7/165 (20130101); F01P 11/20 (20130101); F02B
1/04 (20130101); F01P 2005/105 (20130101); F01P
2005/125 (20130101); F01P 2060/08 (20130101) |
Current International
Class: |
B60H
1/02 (20060101); B60H 1/03 (20060101); F01P
3/20 (20060101); F01P 11/20 (20060101); F01P
7/14 (20060101); F01P 11/14 (20060101); F01P
7/16 (20060101); F01P 5/12 (20060101); F02B
1/04 (20060101); F02B 1/00 (20060101); F01P
5/00 (20060101); F01P 5/10 (20060101); H05B
001/02 (); B60L 001/10 (); H01J 009/00 () |
Field of
Search: |
;219/202,208,205,279
;123/142.5R,142.5E ;237/12.3R,12.3W,12.3C,12.3B |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
J C. Whitney and Co. 1983 Catalog; 1917-19 Archer Avenue, Chicago,
IL, 60680, pp. 7 and 8..
|
Primary Examiner: Bartis; A.
Attorney, Agent or Firm: Seemann; Robert A.
Claims
Having thus set forth the nature of the invention, what is claimed
herein is:
1. In an internal combustion engine vehicle coolant flow system
which includes an internal combustion engine, coolant circulator
pump for pumping coolant heated by the engine from the engine, a
heating radiator for transferring heat contained in the coolant to
an enclosed area of the vehicle, electric blower means for
increasing the rate of heat transfer by the radiator to the
enclosed area and a first piping by which the coolant flow is
established from the coolant circulator pump to the radiator and a
second piping by which the coolant flow is established from the
radiator to the engine, the improvement comprising an auxiliary
heating system including:
a electric pump, connected at its input side to the second piping
for receiving coolant fluid therefrom,
a check valve having an input and an output end,
a conduit for connecting said check valve to the output end of said
electric pump, said check valve being oriented so that its input
end receives fluid from the electric pump for flow therethrough to
its output end and that it will prevent fluid flow back through it
to the electric pump,
a first normally open electrically controlled valve single path
connected at one end to the check valve output and at the other end
to the first piping,
a second normally open electrically controlled valve single path
connected at one end to the check valve output and at the other end
to the first piping at a point spaced from the connection of said
first valve with the first piping, there being no direct through
connection in the first piping between where the two single path
valves join the piping so that fluid flowing from the coolant
circulator pump to the radiator as recited earlier must pass
serially through the valve in flowing through the first piping,
said first and second valves normally being open to fluid flow, and
being closed to interrupt fluid flow when electrically excited,
a electric heating element, mounted sealingly in the conduit and
adapted for receiving electrical current from without the conduit,
for providing heat to the coolant flowing therethrough,
a temperature sensing element connected for interrupting electrical
current flow through the electric heating element when a
predetermined coolant temperature in the auxiliary heating system
is reached, mounted for sensing coolant temperature in said
auxiliary heating system,
means for receiving a first electrical current and,
means for switching the first electrical current on or off to the
electric heating element,
means for selectively switching the first electrical current
through the normally open valves and through the electric pump in
any order of options, among options comprising;
(a) no current through the electric pump and no current through
either valve so that they remain open for permitting unimpeded
coolant flow through the internal combustion engine coolant flow
system by the coolant circulator pump,
(b) current through the electric pump yet not through either valve
so that coolant driven through the check valve by the electric pump
takes two paths, and passes through the first valve then the engine
by way of the first piping and returns to the electric pump by way
of the second piping, while it sumultaneously passes through the
second valve, then the radiator by way of the first piping after
which it returns to the electric pump by way of the second
piping,
(c) current through the electric pump and the second valve to
exclusion of the first valve so that coolant driven through the
check valve by the electric pump passes through the first valve
then the engine by way of the first piping and returns to the
electric pump by way of the second piping and is restricted from
flow to and through the radiator by the closed, second valve,
and
(d) current through the electric pump and the first valve to
exclusion of the second valve so that coolant driven through the
check valve by the electric pump passes through the second valve,
then the radiator by way of the first piping after which it returns
to the electric pump by way of the second piping, and is retricted
from flow to the engine by the closed first valve.
2. The auxiliary heating system as recited in claim 1, wherein said
means for switching electrical current on or off to the electric
heating element is connected for switching current on
simultaneously with current being switched on to the electric
pump.
3. The auxiliary heating system as recited in claim 2, further
comprising means for switching the electrical current on or off to
said electric blower means.
4. The auxiliary heating system as recited in claim 3, further
comprising a temperature sensing element connected for interrupting
current flow through the blower when sensing coolant temperature in
said auxiliary heating system below a predetermined value and
mounted for sensing coolant temperature in said auxiliary heating
system.
5. The auxiliary heating system as recited in claim 4, further
comprising a temperature sensing element connected for interrupting
current flow through the pump when sensing coolant temperature in
said auxiliary heating system below a predetermined value and
mounted for sensing coolant temperature in said auxiliary heating
system.
6. The auxiliary heating system as recited in claim 1, 2, 3, 4, or
5 further comprising, means for preventing successful start of the
internal combustion engine, said means being rendered operative in
response to current being switched on to at least one of the
electric pump or the coolant heating element.
7. The auxiliary heating system as recited in claim 1, 2, 3, 4, or
5 further comprising, means for preventing successful start of the
internal combustion engine, said means being operative in response
to the auxiliary heating system receiving electrical current.
8. The auxiliary heating system as recited in claim 7 wherein;
the electric blower means is of the DC operating type,
said means for receiving the first electrical current is adapted
for receiving AC, and further comprising;
means for receiving a second electrical current, said second
electrical current receiving means is adapted for receiving DC
and,
means for relaying the DC on through the electric blower means,
said relaying means being rendered operative upon the AC being
switched on to the blower means.
9. The auxiliary heating system as recited in claim 7 wherein;
the electric blower means is of the direct current operating type,
and the vehicle includes a DC electric blower current supply
means,
said means for receiving the first electrical current is adapted
for receiving AC and, further comprising;
an AC transformer-isolated input, DC output power supply, connected
for receiving and converting AC into an independent DC for delivery
to the electric blower and,
diode means for assuring mutually exclusive delivery of direct
current to the electric blower means from the direct current output
power supply and the vehicle's internal electric blower DC
supply.
10. The auxiliary heating system as recited in claim 3, 4 or 5
wherein;
the electric blower means is of the DC operating type,
said means for receiving the first electrical current is adapted
for receiving AC, and further comprising;
means for receiving a second electrical current, said second
electrical current receiving means is adapted for receiving DC
and,
means for relaying the DC on through the electric blower means,
said relaying means being rendered operative upon the AC being
switched on to the pump.
11. The auxiliary heating system as recited in claim 3, 4 or 5
wherein;
the electric blower means is of the direct current operating type,
and the vehicle includes a DC electric blower current supply
means,
said means for receiving the first electrical current is adapted
for receiving AC and, further comprising;
an AC transformer-isolated input, DC output power supply, connected
for receiving and converting AC to an independent DC for delivery
to the electric blower and,
diode means for assuring mutually exclusive delivery of direct
current to the electric blower means from the direct current output
power supply and the vehicle's internal electric blower DC
supply.
12. The auxiliary heating system as recited in claim 1, 2, 3, 4, or
5 further comprising a pressure sensing element connected for
interrupting current flow through the electric heating element when
sensing coolant pressure above a predetermined value and mounted
for sensing coolant pressure in said auxiliary heating system; and
means for preventing successful start of the internal combustion
engine, said means being operative in response to said auxiliary
heating system receiving electrical current.
13. In an internal combustion engine vehicle coolant flow system
which includes an internal combustion engine, coolant circulator
pump for pumping coolant heated by the engine from the engine, a
heating radiator for transferring heat contained in the coolant to
an enclosed area of the vehicle, electric blower means for
increasing the rate of heat transfer by the radiator to the
enclosed area and a first piping by which the coolant flow is
established from the coolant circulator pump to the radiator and a
second piping by which the coolant flow is established from the
radiator to the engine, the improvement comprising an auxiliary
heating system including:
a electric pump having a first end and a second end, connected at
the first end to the second piping,
a normally closed electrically controlled valve having a first end
and a second end which opens to permit fluid flow when electrically
excited, electrically connected to the pump so that it opens when
the pump is electrically excited,
a conduit for connecting the first end of said normally closed
valve to the second end of said electric pump,
a first normally open electrically controlled single path valve
connected at one end to the second end of the normally closed valve
and at its other end to the first piping,
a second normally open electrically controlled single path valve
connected at one end of the second end of the normally closed
electrically controlled valve valve and at the other end to the
first piping at a point spaced from the connection of said first
valve with the first piping, there being no direct through
connection in the first piping between where the two single path
valves join the piping so that fluid flowing from the coolant
circulator pump to the radiator as recited earlier must pass
serially through the valves in flowing through the first
piping,
said first and second valves, being normally open to fluid flow,
and being closed to interrupt fluid flow when electrically
excited,
electric heating element, mounted sealingly in the conduit and
adapted for receiving electrical current from without the conduit,
for providing heat to the coolant flowing through the conduit,
a temperature sensing element connected for interrupting electrical
current flow to the electric heating element when a predetermined
coolant temperature in the auxiliary heating system is reached and
mounted for sensing coolant temperature in the auxiliary heating
system,
means for receiving a first electrical current and,
means for switching the first electrical current on or off to the
electric heating element
means for selectively switching the first electrical current
through the normally open valves and through the electric pump in
any order of options, among options comprising;
(a) no current through the electric pump and no current through
either normally open valve so that they remain open for permitting
unimpeded coolant flow through the internal combustion engine
coolant flow system by the coolant circulator pump,
(b) current through the electric pump yet not through either
normally open valve so that coolant driven by the electric pump
simultaneously passes through the engine and radiator in returning
to the pump,
(c) current through the electric pump and the second normally open
valve to exclusion of the first normally open valve so that coolant
driven by the electric pump passes through the engine in returning
to the pump and is restricted from flow through the radiator by the
closed second normally open valve,
(d) current through the electric pump and the first normally open
valve to exclusion of the second normally open valve so that
coolant driven by the electric pump passes through the radiator in
returning to the pump and is restricted from flow to the engine by
the closed first normally open valve.
14. The auxiliary heating system as recited in claim 13, wherein
said means for switching electrical current on or off to the
electric heating element is connected for switching current on
simultaneously with current being switched on to the electric
pump.
15. The auxiliary heating system as recited in claim 14, further
comprising means for switching electrical current on or off to said
electric blower means.
16. The auxiliary heating system as recited in claim 15, further
comprising a temperature sensing element connected for interrupting
current flow through the blower when sensing coolant temperature in
said auxiliary heating system below a predetermined value and
mounted for sensing coolant temperature in said auxiliary heating
system.
17. The auxiliary heating system as recited in claim 16, further
comprising a temperature sensing element connected for interrupting
current flow through the pump when sensing coolant temperature in
said auxiliary heating system below a predetermined value and
mounted for sensing coolant temperature in said auxiliary heating
system.
18. The auxiliary heating system as recited in claim 13, 14, 15, 16
or 17 further comprising, means for preventing successful start of
the internal combustion engine, said means being rendered operative
in response to current being switched on to at least one of the
electric pump or the coolant heating element.
19. The auxiliary heating system as recited in claim 15, 16 or 17
wherein;
the electric blower means is of the DC operating type,
said means for receiving the first electrical current is adapted
for receiving AC, and further comprising;
means for receiving a second electrical current, said second
electrical current receiving means being adapted for receiving DC
and,
means for relaying the DC on through the electric blower means,
said relaying means being rendered operative upon the AC being
switched on to the blower means.
20. The auxiliary heating system as recited in claim 15, 16, or 17
wherein;
the electric blower means is of the direct current operating type,
and the vehicle includes a DC electric blower current supply
means,
said means for receiving the first electrical current is adapted
for receiving AC and, further comprising;
an AC transformer-isolated input, DC output power supply, connected
for receiving and converting AC into an independent DC for delivery
to the electric blower and,
diode means for assuring mutually exclusive delivery of direct
current to the electric blower means from the direct current output
power supply and the vehicle's internal electric blower DC supply.
Description
BACKGROUND OF THE INVENTION
In general this invention relates to electric heating and in
particular to auxiliary heating for an internal combustion engine
vehicle coolant flow system which includes a radiator element for
transferring heat contained in the coolant to an enclosed area.
Cold weather start up of internal combustion engine vehicles has
carried with it numerous costs and inconvenience. The passenger
compartment is an uncomfortable, chilly enclosure when at ambient
temperature, and the windows are frosted. The cold engine is hard
to start because oil is thick and friction is high. When the engine
is started, the friction takes its toll in wear on the parts.
During the warm up period, fuel expenditures is higher, whether
just idling or driving. These problems are inherent to gasoline and
diesel engine type vehicles. Diesel engines, are tougher to start
than gasoline engines and an operator of a large diesel truck often
will leave the motor running for hours at rest stops and during
long waits at delivery depots rather than chance difficult restart
of a cold engine.
The majority of the passenger cars are left on the street over
night. Those that are garaged escape obtaining frosted windows but
little else, for a heated garage is a luxury few care to pay for.
It is more efficient to heat relevant portions of the vehicle
rather than its surrounding environment, and many ways to obtain
that effect have been propounded over the last 70 or so years. The
most common apparatus described for that purpose is an electric
heater which heats engine coolant or its oil by conduction and
convection. For example it may be installed in a hose section which
is, in turn, interposed in the lower radiator hose between the
engine and the radiator used for cooling the engine. Such a device
is announced by J. C. Whitney & Co.; 1917-19 Archer Avenue,
Chicago, IL, 60680, in the 1983 catalog (item 55-2528B, pg. 8).
Similar devices are described in U.S. Pat. No. 1,683,920 issued to
J. E. Rohne on Sept. 11, 1928 and in U.S. Pat. No. 1,267,416 issued
to T. H. Jacob on May 28, 1918. Rhone has the heating element
outside the hose section and Jacob has it located within the
section.
Other conduction and convection type devices include clamp-type
heaters which attach directly to an engine block (J. C. Whitney
item 54-1171T, pg. 7), and freeze plug engine heaters which replace
the freeze plug on the side of the block. (item 55-2363U, pg. 8).
The above devices provide heat primarily to the vehicle's engine
and not to the enclosed area of the vehicle comprising the
passenger and cargo areas.
Installing an electric heating element in the vehicle's heater
radiator and turning on its blower fan prior to use by the driver
is described in U.S. Pat. No. 2,819,373 issued Jan. 7, 1958 to Roy
D. Allman. His device warms the vehicle's enclosed area only, prior
to entry by the driver. A heater with a pump for installation in
the heater return hose is presently available (Whitney; item
54-1262P, pg. 7). This device warms the engine block and the heater
radiator by passing coolant through the two vehicle elements as it
heats the coolant. There is no provision, however, for
automatically transferring heat to the enclosed area. In U.S. Pat.
No. 4,398,081 issued Aug. 9, 1983 to Mark H. Moad, an electric
heating element and pump are connected in series in the coolant
line to circulate the heated coolant first through the heater
radiator, providing the hottest fluid there, and then the engine. A
switch circuit is provided which turns on the heater blower when
the electric heating element is on.
The above and similar devices are limited to heating one area of
the vehicle or tend to give priority to one when both are heated.
Those which include heater, pump or other elements in series within
the vehicle's coolant line may have a deleterious effect on engine
cooling or heater operation when the engine is running. Not only
may the enclosed elements resist smooth fluid flow but they
themselves are subject to the flow during engine operation.
SUMMARY OF THE INVENTION
It is one object of the invention to provide an auxiliary heating
system which may direct the heated fluid with equal priority to
heat the engine and the enclosed, passenger or cargo area.
It is another object of the invention to provide an auxiliary
heating system which may be easily added to an existing vehicle's
coolant circulating system that includes a heater radiator, with
minimal effect upon coolant flow during engine operation.
Another object is to enable one to easily select heating of either
the engine or the enclosed area, or both.
Another object is to effectively isolate the system's pump and
electric heating element from coolant flow during engine
operation.
Another object is to prevent the engine from running when the
system's electric heating element or pump are in operation.
Another object is to minimize power required to operate the system
by relating pump and blower operation to heated fluid
temperature.
Another object is to provide auxiliary direct current suitable for
the vehicle's heater blower and electrically isolated from the
vehicles blower current supply when the auxiliary heating system is
operated from an atlernating current supply.
And yet another object of the invention is to provide an auxiliary
heating system for an internal combustion vehicle which
automatically reverts to a condition of minimum resistance to
engine coolant flow when it is powered down.
Other objects and advantages of the invention will become readily
apparent to persons versed in the art from the ensuing description
thereof.
In accordance with the invention there is provided an auxiliary
heating system for use in an internal combustion engine vehicle's
coolant flow system which includes an internal combustion engine,
coolant circulator pump and a radiator for transferring heat
contained in the coolant to an enclosed area such as the passenger
compartment, and a blower for increasing the rate of transfer. In
the auxiliary heating system, an electric heating element for
heating the coolant and a pump are provided. The pump receives
coolant from the piping through which coolant is returned to the
engine from the heater radiator, and operates to deliver
electrically heated coolant through a check valve to a pair of
normally open, electrically controlled valves. The output ends of
the valves are interposed in the piping which provides coolant flow
from the circulator pump to the heater radiator, so that the
coolant flows serially through the valves on its way to the heater
when the engine is running. The check valve prevents the coolant
from by-passing the heater radiator by passing through the electric
heater and pump. Alternatively to the check valve, a normally
closed electrically controlled valve may be used. For that purpose
it is wired so that it opens whenever current is switched to the
electric pump. When the auxiliary heating system is operating, the
electrically heated coolant is directed, by selectively operating
the two valves, either through the heater radiator in the direction
characteristic to normal running engine coolant flow, or through
the engine in a reverse direction to normal engine coolant flow, or
both of the above simultaneously.
Additionally the invention provides switching for turning on the
blower and in another embodiment includes a power supply for
running the blower within it's operating current parameters while
the auxiliary heating system may be operating under different
current parameters. Coolant temperature sensing elements are
provided to prevent overheat and to save energy by shutting down
the blower when coolant temperature is below a predetermined
level.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be more fully comprehended it will
now be described, by way of example, with reference to the
accompanying drawings, in which:
FIG. 1 is a diagrammatic and schematic representation of the
invention installed in an internal combustion engine vehicle's
coolant flow system showing the invention and pertinent parts of
the vehicle's system.
FIG. 2 is a schematic representation of the power supply for
providing current of the type used by the heater radiator
blower.
FIG. 3 is a diagrammatic and schematic representation of another
embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before explaining the invention in detail it is to be understood
that the invention is not limited in its application to the details
of construction and arrangement of parts illustrated in the
drawings since the invention is capable of other embodiments and of
being practiced or carried out in various ways. It is also to be
understood that the phraseology or terminology employed is for the
purpose of description and not of limitation.
Referring to the drawings, there is shown an internal combustion
engine 1 which incorporates a coolant circulator pump 44 the
dual-output connector 2 for which may be seen at the top of the
block. When the engine is running, coolant which has absorbed its
heat leaves the circulator in two paths; one path is through piping
3, engine cooler radiator 4 where heat is dissipated to the outside
environment, and back to the engine by piping 5, the other path is
through piping 6, normally open electrically controlled valve 7,
piping 8, normally open electrically controlled valve 9, piping 10,
heater radiator 11 where heat is transferred to the vehicle's
enclosed area such as passenger compartment (not shown) and back to
the block by piping 12 as shown by the broken arrows in FIG. 1. The
engine cooler radiator 4 is shown here for clarification purpose in
that it it differentiates from heater radiator 11. Heater blower 13
increases the rate of heat transfer to the vehicle's enclosed area
by heater 11. It is shown connected in FIG. 1 by DC positive line
14 to normally open electrical relay 15. When relay 15 is closed,
it permits current to flow to the blower from the vehicle's
fan-controlling direct current supply line 16. The blower DC
circuit is returned to that supply's ground by line 17.
When the auxiliary heating system is operating, pump 18 receives
coolant from piping 12, by way of piping 19 through junction 20 and
pumps it through piping 21 into conduit 22 which contains electric
heating element 23. The coolant continues to flow through
connection 24, through check valve 25 and ito junction 26 where its
flow divides through normally open valves 7 and 9 as shown by the
solid arrows in FIG. 1. The motor's coolant circulator pump is
inoperative, for reasons which will be explained later. In a
preferred embodiment, the auxiliary heating system is operated on
wall current of 110 volts AC, although the vehicle's accessory and
engine circuit is 12 volts DC. Electrical plug 27 provides the AC
current to three-pole-four-position switch 28. The grounded side of
the plug line is made auxiliary heating system ground, `floating`
or independent from the vehicle's DC circuit. When the ganged poles
of switch 28 are in position (a), it can be seen that valve 7, 9
and pump 18 are not supplied with energizing current. This leaves
the valves open, the pump off and the vehicle's coolant system in
condition for normal engine-circulator driven coolant circulation.
Check valve 25 effectively isolates the auxiliary heating system
coolant heating and pump portions from the coolant arriving at
junction 26 under relatively higher circulator pressure.
Normally closed relay 30 admits vehicle DC current to operate
starting relay 31 for motor starter 32. While it is activated,
relay 30 remains open, preventing engine start by disabling the
starter relay. Electrical line 29 automatically brings energizing
current to normally closed relay 30 as long as the auxiliary
heating system is connected to a live external AC circuit. It is to
be understood that relay 30 may be located so as to control an
ignition coil to prevent a gasoline engine from running while the
relay is activated. It is also to be understood that the engine may
be controlled for the same purpose by including an electrically
operated normally open fuel control valve instead of relay 30.
When switch 28 is in position (b), valve 7 and 9 are not energized
and are open. Heating element 23 receives current from line 33
after it passes through temperature sensing element 34 and pressure
sensing element 35. Temperature sensing element 34 passes current
until a predetermined temperature is reached. Pressure sensing
element 35 performs the safety function of opening the circuit if a
predetermined pressure is reached. Pump 18 is energized by
receiving current via line 33 and temperature sensing element 36.
Temperature sensing element 36 conducts current once a
predetermined minimum operating temperature is reached for
economical and efficient pump operation. In the mean time the
engine circulator is not operating and the coolant flow urged by
pump 18 divides through valves 7 and 9 as explained earlier, taking
divergent paths. Through valve 9 it flows through piping 10,
through heater radiator 11, piping 12, junction 20 and back to the
pump through piping 19. Through valve 7 it flows in a direction
opposite to that of engine operating flow, traveling by way of
piping 6, and output connector 2, through the engine and back to
the pump by piping 12 and 19. Both the engine and heater radiator
coolant flow paths receive freshly heated coolant.
When switch 28 is in position (c), valve 7 is not energized while
valve 9, the heating element and pump are energized. Valve 7 is
therefore open, permitting heated coolant flow through the engine
only, warming the engine. Valve 9 is closed.
When switch 28 is in position (d), valve 9 is not energized, while
valve 7, the heating element and pump are energized. Valve 9 is
therefore open, permitting heated coolant flow through the heater
radiator only, for heating the vehicle's enclosed area. Valve 7 is
closed.
Heater radiator blower 13 is operative when switch 28 is in (b) and
(d) positions. Line 37 provides current to relay 15 by way of
temperature sensing element 38 and line 43. Temperature sensor 38
conducts current once a predetermined minimum operating temperature
is reached for economical and efficient closed area heating. In the
embodiment shown in FIG. 1, the blower receives operating current
from the vehicle's main or auxiliary battery (not shown).
Referring to FIG. 2, the electrically isolated AC input, DC output
power supply circuit "A'" may replace relay 15 circuit "A", if it
were expected that blower 13 would be run for an extended time
resulting in excessive drain on the vehicle's battery DC current
supply. Transformer 39 isolates DC power supply 40 from the AC
supply circuit. Diode 41 isolates the DC supply's output circuit
from the vehicle's DC current and diode 42 protects the vehicle's
DC source from power supply current flow. The two sources are
thereby made independent from each other. Although they share the
same DC current return line from the blower, each may provide
current at different DC voltages to the blower without damage to
the other.
In another embodiment of the invention, referring now to FIG. 3,
pump 18 delivers freshly heated coolant to heater 11 and motor 1 by
way of piping 19, junction 20 and piping 12. Flow control for
heating one or the other or both is provided by valves 7 and 9 as
described earlier, as coolant must flow back to conduit 22 by way
of the valves. The valve 25 of FIG. 1 is changed in this embodiment
to a normally closed electrically controlled valve 25A,
electrically connected to line 33 so that it opens when current is
switched to the pump. Closed, it effectively isolates the auxiliary
heating system's coolant heating and pump portions from the
engine-circulator-driven coolant arriving at junction 26. FIG. 3
illustrates this embodiment wherein valve 25A is the normally
closed electrically controlled valve. It is electrically connected
to AC line 33 so that it is energized whenever AC current is
switched to electric pump 18. It's electrical return is through AC
ground.
From the foregoing description of the invention it will be seen
that an auxiliary heating system for an internal combustion engine
vehicle is provided which will direct the fluid it heats with equal
priority to heat the engine and the enclosed, passenger or cargo
area; that is easy to add to an existing vehicle's coolant flow
system with minimal effect upon coolant flow during engine
operation; provides selection of heating engine, enclosed area or
both; is electrically independent from the vehicles electrical
system; operates with maximum efficency and automatically enables
the vehicles coolant system for normal engine operation when it is
disconnected from the external power source.
Although the invention has been described in specific terms it will
be understood that various changes may be made in size, shape and
materials and in the arrangement of the parts without departing
from the spirit and scope of the invention as claimed.
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